Improvement in bleaching compounds



UNITED STATES PATENT OFFICE- THOMAS DE DIENHElM BI ooHocKI, ornoonoe'nn, FRANCE.

'l-MPROVEMENT -IN BLEACHINGTCOM PO'UNDS.--

Specification forming partof Letters Patent No. 212,890, dated MarohA,1879; application filed May 28, 1877; patented in France, November 15,1876. i

@To, all whom it may concern:

Be it known that I, M. Le Comte THOMAS DE DIENHEIM BROOHOOKI, ofBoulogne-surcrystallized, or annular, {or in cake, iutbej followingmanner: A concentrated alkaline lye of soda or potassa is cooled, andthi-ough it-'is passed a 'current'ot chlorine gas previously cooledand'washedin cold water until the lye becomes almost completelysaturated,

,being kept cool throughout the operation by the immersion of thevessels employed in a bath of water which is kept at a low temperature,not exceeding SO Fahrenheit. Atthe en d of about twen ty-four hours there is obtained a crystallized product possessing powerful bleachingproperties. The mother-liquor concentrated by evaporation in vacuo beingagain cooled vwill furnish an additional quantity of the crystals. p

Another method is to pass-a current of chlorine over athin layer ofalkaline carbonate spread over surfaces kept cold ina close vessel. Thechlorine issuing fromflthi's vessel is passed through a very strong. lyeof oxideof "the samealkali as that in the carbonate, and this'lyellkeptconstantly fc'oo'l readily absorbs" the chlorine, producinghypochlorite. ,By a lateral openin gthatcan be hermetically closed,

'fresh quantities of carbonate arei'ntroduced into the first vessel fromtime to time, when the material therein is supposed-to be nearlysaturated, and thus the risk of decomposition is avoided. The liquidhyp'ochlorite produced in the secondy-essel being mixed witlrpartiallysaturated carbonate in the first, there is ob tai'ned a new product,which is solid and crystalline, the carbonate taking up the water of thehypochlorite solution, so asto fix the} hypochloric acid in a solidform, and in quantity depending on the proportions in which the liquidhypochlorite and the partially-saturated carbonate are mixed together.

For-.the purpose of, solidifying the hypo chlorite solution thecarbonate may be used without being in the first place exposed tochlorine, and may be employed for the same purpose; but in such case theproduct is'less strong in chlorine. V

Th ol dified premed tatedpalettes: 9i the'methods above described isulhite in color, but may be colored as desired. It retain s 'ts j thanany of 'he' bleaching properties longer 1 liquid hypochlorites it may beprepa ed for commerce in the condition of agranil ar salt by merelyagitating the solution when it be comes pasty, or in cakes by runningthe pasty mass into molds and allowing it to solidify at lowtemperature, the molds being for thatpurpose iced. It can be easilypacked and transported, as in the solid condition it does not aflectmetals nor organic substances. For use it is dissolved in 0 1d Waterwitlrfacility.

Having thus desgribed the nature of my invention, and in whatmanner thesame is to be performed, Iv claim As an improvement in compounds usedfor bleaching purposes, as eau de J avelle, a solidcompound produced bysaturating a solution of protoxide of sodium with chlorine gas, and

adding "to; the'i hypochlorite thus produced ctweuty' 'to-"forty per Tcent; of desiccated car-- bonate ot'soda, substantially as described.

Iuwitness whereof I, the'said Comte TrtoMAs DE DIENHEIM Bnoo'nooin, havehereunto set my hand this 17th day of April, 'A.D. 1877.

CT. THOMAS DE DIENHEIMBROOHQCIQ- Witnesses:

ARMENGAUD, Jeune, Rom. M. HOOPER.

